IGNITLON SYSTEM -Troubleshooting 8-109
TROUBLESHOOTING
NOBGH--
Symptom Probable cause
Remedy
Reference
paw
Engine will not start or
Incorrect ignition timing
8-111
hard to start (cranks Adjust ignition timing
OKI Ignition coil faulty
Inspect ignition coil 8-116
Ignition faulty
Inspect igniter
8-120
Distributor faulty
Inspect distributor 8-120
High tension cord faulty
Inspect high tension 8-116
cord
Spark plugs faulty Replace plugs 8-115
Ignition wiring disconnected or broken
Inspect wiring -
Rough idle or stalls
Spark plugs faulty
Replace plugs 8-115
Ignition wiring faulty
Inspect wiring -
Incorrect ignition timing
Adjust ignition timing
8-111
Ignition coil faulty
Inspect ignition coil 8-116
Ignition faulty
Inspect igniter 8-120
High tension cord faulty
Inspect high tension 8-116
cord
Engine hesitates/poor
acceleration Spark plugs faulty Replace plugs 8-115
Ignition wiring faulty
Inspect wiring -
Incorrect ignition timing
Adjust timing 8-111
Poor gasoline mileage
Spark plugs faulty Replace plugs 8-115
Incorrect ignition timing Adjust ignition timing 8-111
Engine overheats Incorrect ignition timing
Adjust ignition timing
8-111 1 STB Revision
IGNITION SYSTEM - Ignition Svstem 8-115
Good No good
721017
72T06t
16W947
SERVICE POINTS OF REMOVAL
l-4. CAUTION OF SPARK PLUG CABLES17. HIGH TENSION
CABLE
The cable is to be pulled out by grasping the cap part.
9. REMOVAL OF DISTRIBUTOR
Before removing the distributor, position the piston in No.
1 cylinder at the top dead center on compression stroke by
the following procedure.
(1) Remove the cap from the distributor.
(2) Turn the crankshaft until the distributor rotor lines up
with the No. 1 spark plug cable electrode on the
distributor cap.
(3) Align the notch on the crankshaft pulley with the timing
mark “T” on the timing indicator to set the engine
SO
that the piston in No. 1 cylinder is at the compression
top dead center.
INSPECTION
CLEANING AND INSPECTION OF SPARK PLUGS
1. Pull the spark plug cables out of the spark plugs.
2. Using a spark plug wrench, take all the spark plugs out of the
cylinder head.
Caution
Ensure that no foreign bodies fall from the spark plug
holes.
3. Using the following criteria check that there is no electrode
spark loss, that there is no damage to the outer insulation, and
that sparking is good.
l Existence of insulation damage
l Spark dissipation
l Carbon accumulation
Using either plug cleaner or wire brush, clean both the up-
per part and the glass part.
l Damage to or breakage of gaskets
l Spark action in spark glass area
In cases where there are black deposits due to carbon, this
indicates excessive passage of mixed gases so that air in-
take becomes extremely deficient.
Owing to the excessively large spark gap, spark loss and so
on can be expected.
In case of white scorching, this indicates an excessively
thin gas mixture and prolongment of sparking time, which
suggests poorly fitted plugs.
/ STB Revision
1
8-116 IGNITION SYSTEM-Ignition System
Plug
cleaner
OlUOO89
Plug gap
gauge NIPPON
termine
rl
direction
High voltage
terminal
01R0234
4. Clean with plug cleaner. Sand which has accumulated in
the screw thread of the plugs is blown out by compressed
air.
5. Using the plug gap gauge, check whether the plug gap reading
is normal, and if not, adjust it.
Standard value : 1.0-1.1 mm (.039-.043 in.)
CHECKING SPARK PLUG CABLE
(1) Check that there are no cracks in the cap or in the insulating
coating.
(2) Ctieck the resistance value.
High tension
cable Spark plug cable
No.1 1 No.2 1 No.3 1 No.4
I 9
I
11
I 13 I 14
CHECKING THE IGNITION COIL
(1) Measurement of the resistance of the external resistor
Measure the resistance of the external resistor. Standard value : 1.2-1.4 IR
(2) Measurement of the resistance of the primary coil
Measure the resistance between the positive (+) terminal
and the negative (-) terminal of the ignition coil. Standard value : 1.1-1.3 IR
(3) Measurement of the resistance of the secondary coil
Measure the resistance between the high voltage terminal
and the positive (+) terminal of the ignition coil. Standard value : 14.5-19.5 kfl
wision I
